Every spring I would be fine all day and then lie down at night and suddenly my nose was a faucet. I thought I was allergic to my pillow. I washed everything. I got dust mite covers. Nothing helped.

Turns out it is not your bedding. It is everything you brought into your bedroom during the day. Pollen does not just float outside — it rides in on your hair, your clothes, your skin, and even your eyelashes. When you lie down, all of that pollen transfers to your pillow and you spend eight hours breathing it in.

The evening shower rule

If you only do one thing, shower before bed. Not in the morning — at night. Rinse the pollen off your skin and out of your hair. Morning showers are for waking up. Evening showers during pollen season are for not sleeping in a cloud of allergens. This single change cut my nighttime allergy symptoms in half.

The bedroom clothes rule

Do not wear your daytime clothes into bed. Do not even toss them on a chair in the bedroom. Strip in the bathroom after your evening shower and put on clean pajamas that have been stored in a closed drawer. Your daytime clothes are covered in pollen. Keep them out of the room where you sleep.

Wash your face and hands before you touch your pillow

Even if you cannot shower, at least wash your face and hands. Pollen sticks to the oils on your skin. Your face presses into your pillow for hours. If you wash your face first, you are not rubbing pollen into the fabric you will be breathing against all night.

Other things that make a difference

• Keep the windows closed in spring, especially at night. Morning pollen counts are highest but evening air still carries plenty. Run an air purifier in the bedroom instead.
• Change your pillowcase every other night during peak pollen season. You do not need to wash the whole bedding set — just swap the pillowcase. Keep a stack of extras.
• A saline nasal rinse before bed flushes pollen out of your nasal passages. It is not fun but it works immediately.
• Keep pets off the bed during pollen season. Dogs and cats are pollen magnets. They roll in grass and then jump on your pillow.

I used to think nighttime allergies were a separate thing from daytime allergies — like some mysterious indoor trigger I could not find. It was the same outdoor pollen the whole time. I was just marinating in it for eight hours on my own pillow.